Tool



April 8 1924.

C. E. SUTTON TOOL Filed May 2, 1923 Patented Apr; '8, 19 24 PATENT oFFlcE.

c a asn E. sermon, on LOS aNeEnES, camroan'm.

TOOL.

- of well apparatus, more particularly drill stems, and has for its main object the provision of an improved overshot fishing tool. The invention resides in the construction and the details of such a tool an embodiment of which is described by the following specification and illustrated by the accompanying drawings in which:

Fig. 1 is a longitudinal sectional view showing the application of the tool to recovers. broken drill stem;

Fig. 2 is cross section on the line 22 of Fig. 1;

ig. 3 is a cross section on the line 33 of Fi 1;.and ig 4 is a. fragmentary longitudinal section showing the position of the packing around the drill stem when the tool is in position to remove the drill stem.

Referring to the drawings in detail, the reference character 10 designates an overshot bowl or carrier of cylindrical form which is threaded at its upper end to receive a coupling 11 to which is detachably connected a. wash pipe or line of tubing 12 by 85 which the carrier may be lowered into the well or hole to the desired depth. The lower end of the carrier 10 is also threaded to receive a guide shoe 13 to facilitate the aiding of the tool in the well and aroun the part to be recovered which, as shown by the drawings, comprises a drill stem 14 which, as is usual, is provided with one or more collars or joints 15, only one of such joints being shown by the drawings.

The carrier 10 is provided with a plurality of vertical slots 16 in which are slidably positioned the vertical ends 17 of the inclined spring dogs 18, the lower ends of said dogs being secured to an upper ring 19 by means of screws 20. The slots 16 extend to the upper end of the carrier and mounted in these slots above the vertical ends 17 of the dogs 18 are retaining or hold down keys 21 to prevent the top ring 19 and the spring Application filed May 2,

1923. Serial no, 636,247.

dogs 18 from being caught on the drill stem 14 or its collar or joint 15 when the tool is lowered into the well or hole.

The carrier 10' is also provided with a lower ring 22 which rests on an internal annular shoulder of the carrier as shown. Positioned between the top and bottom rings 19 and 22 are two packing rings 23 and 24, preferably of rubber, the lower packing ring being provided with a tapered opening as shown at 25, said packing rings having cooperating bevelled ends as shown at 26.

In use the apparatus or tool is lowered into the well or hole until the spring dogs 18 pass over the first collar or tool joint 15 so that when carrier is subsequently drawn upwardly, the ends of the dogs engage the collar or joint 15, as shown more clearly by Fig. 1. When the carrier 2 is further pulled, the lower ring 22 compresses and contracts the packing ring 24 around the drill stem 14, the carrier being designed so that when the packing 24 is in the position shown by Fig. 4 so as to act as a fluid seal between the carrier 10 and the drill stem 14, the upper internal annular shoulder 27 of the carrier will engage the bottom ends of the dogs 18. If an adequate ull on the carrier 10 does not succeed in islodging the drill stem 14, pumps at the surface of the well or hole may be connected to the wash pipe or tubing 12 and oil, water, mud, or other fiuidmay be forced down through the drill stem and out around the bit or other tool at the bottom of the drill stem, the fluid passing to the lower surface of the packing 24 which forms a fluid tight joint with the driil stem. The fluid by its pressure against the packing exerts a powerful force to loosen the drill stem, after which the latter may be withdrawn by a mechanical force applied to the carrier, as is obvious.

From the above description, it is believed that the construction and operation of the tool are apparent. Although a specific embodiment of the invention has been shown and described for the purpose of illustrating the invention and disclosing what is considered the best mode of reducing the invention to a practical form, it is to be understood that certain changes in the details of the construction may be made, but all such changes are to be considered as part of my invention as defined by the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1'. A fishing tool comprising a carrier having circumferentially spaced vertical slots therein, a sleeve slidable in said carrier, a plurality of spring dogs secured to said sleeve having their lower ends slidably positioned in said carrier slots and their upper ends inclined to en age a projection on a tool to be removed rom a well, and retaining keys positioned in said carrier slots and adapted to bear on the lower ends of said spring dogs.

2. fishing tool comprising a carrier having upper and lower sleeves slidable therein and adapted to surround a drill stem to be removed from a well, and a packing positioned between said upper and lower sleeves and adapted to make a fluid tight joint between said carrier and the drill stem, said packing comprising two rings in contiguous relation, one of said rings being adapted to be moved by said lower sleeve between the other ring and the drill stem whereby a fluid tight joint between the carrier and the drill stem is formed.

3. A fishing tool comprising a carrier, an upper ring slidable therein, spring dogs secured to said upper ring and adapted to-engage a projection on a drill stem to be removed from a well, a lower ring slidable in said carrier, and a packing between said upper and lower rings adapted to surround said drill stem and to form a fluid tight joint between the carrier and the drill stem, said packing consisting of two rings, and one of said rings having a cut out portion and being adapted to be moved by the lower ring into position between the other of said packing rings and the drill stem.

In testimony whereof, I hereunto afiix my signature.

CHASE E. SUTTON. 

